It's all subjective (also has to do with your setup)! For example, I cannot for the life of me understand how people handle 50% or above PG.. even 50% is ahhhhh. It murders my throat past 50%. My personal sweet spot is 70/30 VG to PG, I get the flavor, smoothness, and a satisfying cloud. I also sub-ohm and take lung hits, simply feels weird to me amassing the vapor in my mouth and then inhaling, makes me cough.
60/40 VG to PG is pretty decent as well, I tend never to get a throat hit with it and for the sweeter juices it helps bring out the flavor more. Anything 70% VG or above though, will gunk up your coils quicker, especially with darker/sweeter juices. 80%+ is generally for dripping, it'll kill most coils 2x faster.
Remember! VG is for smoothness and cloud density, while PG is for throat hit, nicotine content, and a preservative to allow your juices a longer shelf life.